today the hearings began for the soldiers facing murder charges accused of killing three afghan civilians and the interrogation tapes you see a painted picture of american infantry man who smoked hash at night and killed for sport during the day. drew griffin investigates for tonight's "special investigation. >> reporter: corporal jeremy more locke is accused of killing three afghan civilian men. two by shooting and the third, as described to a military investigator, was literally a set-up he says, by his platoon leader, staff sergeant calvin gibbs. >> we went to his compound. they walked him out and set him in place, and like, hey, stand here. >> he was fully cooperating? >> yeah. >> was he armed? >> no. >> where did he sit him? >> next to a wall. that's where gibbs could get like behind cover after the grenade went off and then -- off over here out of line of sight. and you know, he pulled out one of his grenades, american grenade, you know, pop the it and throws the grenade and then tells me and [bleep] all right, dude, watch this guy.